Ionic vs. Covalent Review Symbols in Equations Translating Equations

Objectives – Today I will be able to: Apply ionic and covalent naming rules to naming compounds Identify symbols commonly used in equations Identify the 7 diatomic elements Translate an equation from words to symbols Informal assessment – monitoring student interactions as they complete the review game and translating practice Formal assessment – analyzing student responses to the translating practice and exit ticket Common Core Connection – Build Strong Content Knowledge

Lesson Sequence Evaluate: Warm-up Explain: Symbols in Equations Notes Elaborate: Translating Equations Practice Evaluate: Exit Ticket

Warm Up What are the 5 pieces of evidence for a chemical change? Name the following compounds Mg 3 (PO 4 ) 2 PBr 3 CCl 4 PbS

Objectives Today I will be able to: – Apply ionic and covalent naming rules to naming compounds – Identify symbols commonly used in equations – Identify the 7 diatomic elements – Translate an equation from words to symbols

Homework Finish Translating Equations Practice If you are uncomfortable with ionic vs. covalent naming – Review Ionic vs. Covalent Naming Who wants to be a millionaire review game Lab Wednesday – Wear Closed Toe Shoes!!

Agenda Warm-up Symbols in Equations Translating Equations Practice Exit Ticket

Review

How many elements are in the compound Cu(OH) 2 ?

3

How can we tell apart different elements?

Each new element begins with a capital letter

What does the number 4 in NH 4 represent?

It tells us that there are four hydrogen atoms This is called a subscript

How many atoms are in the compound Mg(C 2 H 3 O 2 ) 2 ?

15

Symbols in Chemical Equations

Process of one or more reactants converting to form products with different properties. What is a chemical reaction?

Using words – Hydrogen (gas) + Oxygen (gas)  water (liquid) Using symbols – 2H 2(g) + O 2(g)  2H 2 O (l) Symbols are a shorthand way to represent an equation Ways to Represent Chemical Equations

What is written on the left side of the equation?

Reactants H 2 + O 2  H 2 O

What is written on the right side of the reaction?

Products H 2 + O 2  H 2 O

Coefficient Determines the quantity of each compound present in a reaction Written in front of the compound Example:

How is a coefficient different from a subscript?

A coefficient tells us how many of each compound are present in a reaction while a subscript tells us how many of each atom there are.

What is the coefficient in 4H 2 ?

4

What is the subscript in 2NH 3 ?

Other symbols in equations SymbolExampleWhat does it mean?  2H 2 + O 2  2H 2 O “produces” or “yields”, indicates result of reaction (s) PbCl 2(s) Compound is a solid (precipitate) (l) HCl (l) Compound is a liquid (g) H 2(g) Compound is a gas (bubbles) (aq) NaCl (aq) Compound is soluble (dissolves) in water but is a solid when not in a solution Reaction in which products can reform into reactants, can go both ways

SymbolExampleWhat does it mean?  Heat is applied, may have word “heat” instead of triangle  Other conditions (temperature, pressure, etc.) may be indicated here, or below the arrow Δ

7 Diatomic Elements More Stable for them to exist with 2 bonded together H 2 N 2 O 2 F 2 Cl 2 I 2 Br 2

Translating Equation Practice Practice translating the equations from words to symbols

Exit Ticket Translate the following equation: – Solid mercury (II) oxide breaks down when heated, forming the elements mercury and oxygen.